Semiconductor device and method of manufacture thereof, circuit board, and electronic instrument

ABSTRACT

A method of manufacture of a semiconductor device comprises a step of providing an adhesive ( 30 ) between a semiconductor chip ( 20 ) and a substrate ( 10 ), a step of positioning electrodes ( 22 ) and leads ( 12 ) to oppose each other, and a step of applying pressure in the direction of making the gap between the semiconductor chip ( 20 ) and substrate ( 10 ) narrower, and on the substrate ( 10 ), in a region opposing the surface of the semiconductor chip ( 20 ) and avoiding the leads ( 12 ), a film ( 14 ) is formed with lower adhesion with the adhesive ( 30 ) than the substrate ( 10 ).

TECHNICAL FIELD

The present invention relates to a semiconductor device and method ofmanufacture thereof, to a circuit board, and to an electronicinstrument.

BACKGROUND ART

The method of using an anisotropic conductive film for electricalconnection between substrates is well known. Japanese Patent ApplicationLaid-Open No. 4-317347 describes the bonding of a semiconductor chip andsubstrate in which this method is applied to flip-chip bonding.

A resin-based adhesive such as an anisotropic conductive film has highadhesion with the substrate, and therefore the adhesive itself has poorflowability, as a result of which holes and voids tend to form in andaround the position of mounting an IC. Holes and voids act as gatheringplaces for moisture, and thus have an adverse effect on reliability.

The present invention solves this problem, and has as its objective theprovision of a semiconductor device and method of manufacture thereof, acircuit board, and an electronic instrument, such that holes and voidsdo not occur in and around the position of mounting an IC.

DISCLOSURE OF THE INVENTION

(1) The method of manufacture of a semiconductor device of the presentinvention comprises the steps of:

-   -   providing an adhesive between a surface of a semiconductor chip        having a plurality of electrodes on which the electrodes are        provided and a surface of a substrate having a plurality of        leads formed on which the leads are formed;    -   positioning at least one of the plurality of electrodes to        oppose at least one of the plurality of leads; and    -   applying pressure in a direction such as to make the gap between        the semiconductor chip and the substrate narrower;    -   wherein on the surface of the substrate on which the leads are        formed, in a region being at least part of a region of adherence        of the semiconductor chip, a film is formed with a lower        adhesion to the adhesive than a base material of the substrate.

According to the present invention, since the semiconductor chip andsubstrate are adhered by the adhesive, bonding of the two is achievedsimply, and moreover, a strong fixing of the two (semiconductor chip andsubstrate) is possible to ensure the electrical connection of theelectrodes and leads. On the substrate, in a region including at least apart of the region to which the semiconductor chip is adhered, a film isformed which has a lower adhesion with the adhesive than the basematerial of the substrate. Therefore, on this film surface, holes andvoids become more easily dispersed, and are reduced in size to atolerable level, whereby a semiconductor device of high reliability canbe manufactured.

(2) In this method of manufacture of a semiconductor device, theadhesive may be formed of an anisotropic conductive material havingconductive particles dispersed in an insulating material.

By means of this, the electrodes and leads can be electrically connectedby the conductive particles, and the electrical connection can becarried out simultaneously with (that is, in the same operation as) theadhesion of the semiconductor chip and the substrate.

(3) In this method of manufacture of a semiconductor device, the leadsand the film may be formed by etching a conductive foil adhered to thebase material of the substrate.

By doing this, the leads and film can be formed simply in a small numberof steps.

(4) In this method of manufacture, a conductive foil used when formingthe leads may also be used to form the film.

(5) In this method of manufacture of a semiconductor device, the filmmay be formed simultaneously with the leads.

(6) In this method of manufacture of a semiconductor device, theelectrodes may be provided on an extremity of the surface of thesemiconductor chip, and the film may be formed in a region opposing acentral part of the surface of the semiconductor chip.

By means of this, since the film with a low adhesion with the adhesiveis formed in the central part in which holes and voids tend to form, alarge benefit is obtained.

(7) In this method of manufacture of a semiconductor device, the filmmay be formed to spread two-dimensionally, with at least one openingexposing a surface of the substrate.

By doing this, since the surface of the substrate is exposed in theopening, in this portion the adhesion of the adhesive is increased, andthe adhesive force between the semiconductor chip and the substrate isincreased.

(8) In this method of manufacture of a semiconductor device, the filmmay be formed to project outside a region in which the semiconductorchip is adhered.

By doing this, holes and voids can easily escape to the exterior bypassing over the portion of the film projecting outside thesemiconductor chip.

(9) In this method of manufacture of a semiconductor device, the filmmay be formed to be symmetrical about a center point of the region inwhich the semiconductor chip is adhered.

By means of this, an adhesion force symmetrical with respect to thesemiconductor chip can be applied. Here by the term “symmetricaladhesion force” is meant a balanced state, or a state with nounevenness.

(10) In this method of manufacture of a semiconductor device, the filmmay be formed to avoid at least one of the leads.

(11) In this method of manufacture of a semiconductor device, a part ofthe film may be formed in a position overlying the electrodes.

Then the film and electrodes may be electrically bonded.

(12) A semiconductor device of the present invention comprises:

-   -   a semiconductor chip having a plurality of electrodes;    -   a substrate on which is formed a plurality of leads; and    -   an adhesive provided between a surface of the semiconductor chip        on which the electrodes are formed and a surface of the        substrate on which the leads are formed, and adhering the        semiconductor chip and the substrate,    -   wherein at least one of the plurality of electrodes and at least        one of the plurality of leads are electrically connected; and    -   wherein on the substrate in a region including at least a part        of the region opposing the semiconductor chip, a film is formed        with a lower adhesion to the adhesive than a base material of        the substrate.

According to the present invention, the semiconductor chip and substrateare adhered by the adhesive, and the electrical connection between theelectrodes and leads is achieved. On the substrate, in a regionincluding at least a part of the region opposing the semiconductor chip,a film is formed, having a lower adhesion with the adhesive than thebase material of the substrate. Therefore, on this film surface, holesand voids become more easily dispersed, and are reduced in size to atolerable level, whereby the reliability is increased.

(13) In this semiconductor device, the adhesive may be formed of ananisotropic conductive material having conductive particles dispersed inan insulating material.

By means of this, the electrodes and leads can be electrically connectedby the conductive particles, and the electrical connection can beachieved with the adhesion of the semiconductor chip and the substrate.

(14) In this semiconductor device, the leads and the film may be formedof the same electrically conductive material.

By doing this, the leads and film can be formed simply in a small numberof steps.

(15) In this semiconductor device, the electrodes may be provided at anextremity of the surface of the semiconductor chip, and the film may beformed in a region opposing a central part of the surface of thesemiconductor chip.

By means of this, since the film with a low adhesion with the adhesiveis formed in the central part in which holes and voids tend to form, alarge benefit is obtained.

(16) In this semiconductor device, the film may be formed to spreadtwo-dimensionally, with at least one opening exposing a surface of thesubstrate.

By doing this, since the surface of the substrate is exposed in theopening, in this portion the adhesion of the adhesive is increased, andthe adhesive force between the semiconductor chip and the substrate isincreased.

(17) In this semiconductor device, the film may be formed to projectoutside a region in which the semiconductor chip is adhered.

By doing this, holes and voids can easily escape to the exterior bypassing over the portion of the film projecting outside thesemiconductor chip.

(18) In this semiconductor device, the film may be formed to besymmetrical about a center point of a region in which the semiconductorchip is adhered.

By means of this, an adhesion force symmetrical with respect to thesemiconductor chip can be applied.

(19) In this semiconductor device, the film may be formed to avoid atleast one of the leads.

(20) In this semiconductor device, a part of the film may be formed in aposition overlying the electrodes.

Then the film and electrodes may be bonded.

(21) on a circuit board of the present invention, the abovesemiconductor device is mounted.

(22) An electronic instrument of the present invention has the abovesemiconductor device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a first embodiment of the semiconductor device according tothe present invention.

FIG. 2 shows the substrate of the first embodiment of the semiconductordevice according to the present invention.

FIG. 3 shows a second embodiment of the semiconductor device accordingto the present invention.

FIG. 4 shows the substrate of the second embodiment of the semiconductordevice according to the present invention.

FIG. 5 shows a third embodiment of the semiconductor device according tothe present invention.

FIG. 6 shows the substrate of the fourth embodiment of the semiconductordevice according to the present invention.

FIG. 7 shows a circuit board on which is mounted a fifth embodiment ofthe semiconductor device.

FIG. 8 shows an electronic instrument equipped with a sixth embodimentof the semiconductor device.

FIG. 9 shows an electronic instrument equipped with a seventh embodimentof the semiconductor device.

FIG. 10 shows details of the seventh embodiment of the semiconductordevice.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is now described in terms of a number of preferredembodiments, with reference to the drawings, but the present inventionis not restricted to these embodiments.

First Embodiment

FIG. 1 shows a first embodiment of the semiconductor device to which thepresent invention is applied, and FIG. 2 shows the substrate used in thesemiconductor device shown in FIG. 1. This embodiment of thesemiconductor device includes a substrate 10, a semiconductor chip 20,and an adhesive 30. The substrate 10 includes a base material, aninterconnect pattern formed on the base material, and a film 14described hereinbelow.

In FIGS. 1 and 2, a part of the substrate 10 is shown cut away, and theoverall shape thereof is not particularly restricted, and may berectangular, polygonal, or a combination of a number of rectangles. Thethickness of the base material of the substrate 10 is commonlydetermined by the material thereof, but this is also not restricted. Thebase material of the substrate 10 may be an organic or inorganicmaterial, or may equally be a composite of the two. As a base materialof the substrate 10 formed of an organic material may be cited, forexample, a flexible substrate formed of a polyimide resin. As a basematerial of the substrate 10 formed of an inorganic material may becited, for example, a ceramic substrate or glass substrate. As acomposite construction of organic and inorganic materials may be cited,for example, a glass epoxy substrate.

On the base material of the substrate 10 is formed an interconnectpattern including a plurality of leads 12. On a part of the leads 12(for example, an end part), if necessary, may be formed lands beingwider than the leads 12, for the purpose of bonding the semiconductorchip 20 with electrodes 22. The spacing between adjacent leads 12 ispreferably at least 30 μm. The leads 12 may be formed at a pitch ofabout 70 μm. It should be noted that in FIG. 2, only those of the leads12 connected to the electrodes 22 of the semiconductor chip 20 or closeto the position thereof are shown, but these leads 12 may be furtherextended and used as interconnects for external connection, or may beconnected to electronic components.

The leads 12 are formed on one surface of the base material of thesubstrate 10, so as to avoid a part (for example, a central part). Forexample, a plurality of leads 12 are formed to surround a partial region(the rectangular region in the example shown in FIG. 2) of the basematerial of the substrate 10. In this case, the leads 12 may be formedat the extremity of the base material of the substrate 10, and leads 12not formed in the central part. Of the plurality of leads 12, a group ofleads 12 may be formed parallel facing in a single direction. Theplurality of leads 12 may be arranged to be parallel aligned inrespective of a plurality of directions. In this case, the plurality ofleads 12 are divided into a plurality of groups of leads 12 aligned in aplurality of directions. It should be noted that the leads 12, inaddition to being formed on one surface of the base material of thesubstrate 10, may also be formed on the other surface.

The leads 12 are formed of an electrically conductive material. As anelectrically conductive material may be cited a metal. For example, theleads 12 can be formed by plating the surface of copper with gold ortin. Alternatively, the leads 12 may be formed of gold.

In the present invention, a three-layer substrate may be used, in whichthe leads 12 are attached to the base material of the substrate 10 withan interposed adhesive. Alternatively, the leads 12 can be formed byforming an electrically conductive film of copper or the like on thesubstrate by sputtering or the like, and then etching this. In thiscase, the leads 12 are directly formed on the base material of thesubstrate 10, in a two-layer substrate with no interposed adhesive. Oran additive method can be applied in which the leads 12 are formed byplating. Alternatively, a built-up substrate of multilayer constructioncan be used, in which an interconnect pattern is laminated to include aninsulating resin and the leads 12, or a multilayer substrate in which aplurality of substrates are laminated.

On the surface of the base material of the substrate 10, the film 14 isformed. The film 14 preferably has lower adhesion with the adhesive 30than with the surface of the base material of the substrate 10. The film14 is formed to avoid at least one or all of the leads 12. The film 14is formed so as not to contact at least one or all of the leads 12. Ofthe plurality of leads 12, not all but at least one may contact the film14. For example, by contacting leads 12 to be connected to groundpotential (GND potential) with the film 14 so as to be electricallyconductive, the whole of the film 14 may be at ground potential (GNDpotential). In this case, since the film 14 which is larger than theleads 12 is at ground potential (GND potential), sudden variations inthe potential thereof can be absorbed. Also, the potential of thesemiconductor chip 20 itself is stabilized.

When the leads 12 are formed to avoid a part (for example the centralpart) of the surface of the base material of the substrate 10, in theportion avoided by the leads 12 (for example the central part), the film14 can be formed. The form of the film 14 may be any of a rectangle, apolygon, or a combination of a plurality of rectangles.

The film 14 is formed in a region opposing the surface of thesemiconductor chip 20 on which the electrodes 22 are formed. The film 14is formed in a region including at least a part of the region contactedby the semiconductor chip 20. In more detail, the film 14 in itsentirety, a part thereof, or at least a part thereof, and the surface ofthe semiconductor chip 20 on which the electrodes 22 are formed overlapin plan view. For example, the film 14 may be formed within the limitsof the surface of the semiconductor chip 20 on which the electrodes 22are formed (within the projection region of the surface on which theelectrodes 22 are formed), and a part of the film 14 may project outsidethat region. If it is projecting, bubbles forming within the adhesive 30are easily dispersed on the film 14 and released to the exterior.

The film 14 may be formed in such a shape as to avoid the electrodes 22of the semiconductor chip 20. Alternatively, it may be formed to overlapa group of the plurality of electrodes 22 (being at least one andexcluding the case of the totality) and make contact. In this case,since the film 14 has a larger area than the leads 12, the relativepositioning of the electrodes 22 and film 14 is easy.

In the example shown in FIG. 2, the film 14 is formed within a region(for example a rectangular region) surrounded by the plurality of leads12. The film 14 is formed in a position including the center point ofthe region of adhesion of the semiconductor chip 20. In particular, seenfrom this center point, the film 14 is preferably formed in a form withsymmetry (point symmetry or line symmetry about a line through thepoint). By this means, a symmetrical adhesion force is applied to thesemiconductor chip 20. The outer periphery of the film 14 and the edgeof the leads 12 are preferably formed so as to leave as large a gap aspossible, and are preferably formed to leave a gap of at least about 25μm to 50 μm, and if there is leeway, more.

The film 14 can be made of an electrically conductive material. As anelectrically conductive material may be cited a metal. For example, thefilm 14 can be formed with gold or tin plating over the whole surface ofcopper. Alternatively, the film 14 can be formed of gold. The metalcommonly has a lower adhesion with the adhesive 30 than the surface ofthe base material of the substrate 10.

On the above described substrate 10 the semiconductor chip 20 ismounted. On the semiconductor chip 20 are formed the plurality ofelectrodes 22. These electrodes 22 preferably have conductiveprojections (bumps) formed. The semiconductor chip 20 has the surface onwhich the electrodes 22 are formed positioned opposing the surface ofthe base material of the substrate 10 on which the leads 12 and film 14are formed. At least one of the electrodes 22 is positioned on a part ofone of the leads 12. If a land is formed on the lead 12, the electrode22 is positioned on the land. The region of the surface of thesemiconductor chip 20 on which the electrodes 22 are formed excludingthe electrodes 22 opposes all, a part, or at least a part of the film14. Of the electrodes 22, at least one not being all may be positionedon the film 14.

The substrate 10 and semiconductor chip 20 are adhered with the adhesive30. The adhesive 30 may have epoxy resin as its main constituent. Theadhesive 30 may be insulating. Alternatively, the adhesive 30 may be ananisotropic conductive adhesive (ACA) containing dispersed conductiveparticles, such as an anisotropic conductive film (ACF) or anisotropicconductive paste (ACP). In that case, between the leads 12 formed on thebase material of the substrate 10 and the electrodes 22 formed on thesemiconductor chip 20, the conductive particles intervene, and providean electrical connection between the two. Alternatively, the leads 12and electrodes 22 may be directly bonded, and the substrate 10 andsemiconductor chip 20 may be adhered with the adhesive 30. The surfaceof the semiconductor chip 20 on which the electrodes 22 are formedopposes the film 14. In this case, conductive projections are preferablyformed on at least either of the electrodes 22 and the leads 12.

The adhesive 30 used here has a lower adhesion with the film 14 thanwith the base material of the substrate 10. Therefore, since theadhesive 30 has a high adhesion with the region of the base material ofthe substrate 10 in which the leads 12 and film 14 are not formed, itforms a strong bond between the substrate 10 and the semiconductor chip20. Since the adhesive 30 adheres to the leads 12 and film 14 with a lowadhesive force, for reasons such as that the flowability is increased,voids and holes tend not to form on the surface of the leads 12 and film14. As a result, the accumulation of moisture in voids and holes can beprevented, and the reliability can be increased.

This embodiment is constructed as described above, and the method ofmanufacture thereof is now described. First, on the base material of thesubstrate 10, the leads 12 and film 14 are formed. The leads 12 and film14 can be formed in separate processes, but are preferably formed in thesame process. For example, a conductive foil such as a metal foil can beformed on the base material of the substrate 10, and this can be etchedto form the leads 12 and film 14 together.

The adhesive 30 is provided on at least either of the surface of thesemiconductor chip 20 on which the electrodes 22 are provided and thesurface of the base material of the substrate 10 on which the leads 12and film 14 are formed. The adhesive 30 may be previously provided in aform of an adhesive tape. As the adhesive 30 can be used an anisotropicconductive material or anisotropic conductive film.

Next, the surface of the semiconductor chip 20 on which the electrodes22 are provided and the surface of the base material of the substrate 10on which the leads 12 and film 14 are formed are opposed. Then of theplurality of electrodes 22 at least one or the totality, and of theplurality of leads 12 at least one or the totality are positioned.Furthermore, pressure is applied in the direction of making the gapbetween the semiconductor chip 20 and the substrate 10 narrower. When asthe adhesive 30 is used an anisotropic conductive material havingconductive particles within a resin, such as for example a solidanisotropic conductive film, then the conductive particles are squashedbetween the electrodes 22 and the leads 12, and pressure is applieduntil there is an electrical connection therebetween. This is fixed sothat the two (the electrodes 22 and the leads 12) are in an electricallyconductive state.

By means of the above process, a semiconductor device can bemanufactured. According to this embodiment, since the semiconductor chip20 and substrate 10 are adhered by the adhesive 30, bonding of both canbe achieved simply, and moreover the electrical connection between theelectrodes 22 and the leads 12 can be achieved. On the base material ofthe substrate 10, in the region opposing the surface of thesemiconductor chip 20, the film 14 is formed with lower adhesion to theadhesive 30 than the base material of the substrate 10. As a result, onthe surface of this film 14, holes and voids are less prone tooccurrence, and a semiconductor device of high reliability can bemanufactured.

Second Embodiment

FIG. 3 shows a second embodiment of a semiconductor device to which thepresent invention is applied, and FIG. 4 shows the substrate used in thesemiconductor device shown in FIG. 3. This embodiment of thesemiconductor device comprises a substrate 40, and the semiconductorchip 20 and adhesive 30 described in the first embodiment. The substrate40 has a modified form of the film 14 of the substrate 10 described inthe first embodiment, and otherwise the construction is the same as thatof the substrate 10, for which reason description is omitted here.

The film 44 of the substrate 40 differs from the film 14 in havingformed at least one opening 46. The opening 46 exposes the surface ofthe base material of the substrate 40, and in form may be circular,rectangular, polygonal, or the like. By forming the opening 46, in atleast a part of the film 49 the surface of the base material of thesubstrate 40 is exposed, and the adhesive 30 enters the opening 46. Bydoing this, the region in which the adhesive 30 adheres to the substrate40 is increased, and the adhesion force between the semiconductor chip20 and the substrate 40 is increased. In particular, rather than forminga single large opening 46, it is preferable to form a plurality ofrelatively small openings 46 at a plurality of positions in the film 44.By doing this, the occurrence of holes and voids in the film 44 can beprevented, and a loss of adhesion force can be avoided. When forming theopening 46 in the film 44, if the film 44 is formed thinly, for examplein the range 8 to 12 μm, it is easy for the adhesive 30 to enter theopening 46, and thus for air to escape, and this is thereforepreferable.

For the method of manufacture of this embodiment of the semiconductordevice, the method described in the first embodiment can be applied. Ifa metal foil or conductive foil is etched to form the leads 12 and film44, the opening 46 can be formed at the same time.

Third Embodiment

FIG. 5 shows a third embodiment of the semiconductor device to which thepresent invention is applied. This embodiment of the semiconductordevice comprises a substrate 50, and the semiconductor chip 20 andadhesive 30 described in the first embodiment. The substrate 50 is thesubstrate 10 described in the first embodiment, in which through holes52 are formed, and leads 54 are formed on the surface opposite to thatof the leads 12, and since otherwise the construction is the same asthat of the substrate 10, description is omitted here.

The through holes 52 are formed between some of the plurality of leads12 formed on one surface of the base material of the substrate 50 andsome of the plurality of leads 54 formed on the other surface of thebase material of the substrate 50. Each of the through holes 52 isprovided with a conductive material by plating of gold or the like or bysoldering, so that the leads 12 and 54 on both side of the substrate 50are electrically connected. On the leads 54 formed on the other surfaceof the base material of the substrate 50 may be formed externalelectrodes 56 as solder balls or the like. Equally, without formingsolder balls the leads 54 themselves may serve as external terminals.Otherwise for the construction and the method of manufacture may beapplied the same construction and method of manufacture as in the firstembodiment.

The presence of the film 14 means that the occurrence of warping of thesubstrate which could occur when the film 14 is not present on aflexible substrate such as for example a polyimide substrate can belimited. When the film 14 is not formed on the base material of thesubstrate, and particularly when the substrate is such as to haveflexibility, then the problem of warping of the substrate itself occurs,but by the provision of the film 14 the excellence of strength can bemaintained. In other words, by the adoption of the present constructionwhereby the generation of bubbles can be restricted, flatness can beadequately ensured on the surface on which the external terminals areformed. Therefore, the reliability in external connection can also beimproved.

Fourth Embodiment

FIG. 6 shows a fourth embodiment of the substrate used in thesemiconductor device to which the present invention is applied. Asubstrate 110 has a film 114 having a modified form of the film 14 ofthe substrate 10 described in the first embodiment.

The substrate 110 has a plurality of leads 112 formed, and the film 114is formed so as to be interleaved with the leads 112. For example, apair of leads 112 are aligned parallel, and the film 114 is formed witha projection 116 entering therebetween. On the film 114 are formed aplurality of projections 116. The projections 116 and leads 12 arepreferably formed with as large as possible a gap therebetween, and forexample preferably there is a gap of approximately 25 μm to 50 μm.Otherwise the construction is the same as in the substrate 10, anddescription is omitted here. In this embodiment also, the benefit of thefirst embodiment can be achieved.

Fifth Embodiment

FIG. 7 shows a circuit board 1000 on which is mounted a fifth embodimentof the semiconductor device 1100 to which the present invention isapplied. For the circuit board an organic substrate such as for examplea glass epoxy substrate is commonly used. On the circuit board, isformed an interconnect pattern of for example copper formed into adesired circuit, and by the mechanical connection of this interconnectpattern to the external electrodes of the semiconductor device, theelectrical conduction is achieved.

Sixth Embodiment

As an example of an electronic instrument to which the present inventionis applied, FIG. 8 shows the substrate 10 on which the semiconductorchip 20 is mounted, with a liquid crystal panel 60 fitted. Thesemiconductor chip 20 is the driver for the liquid crystal panel 60.

Seventh Embodiment

FIG. 9 shows a seventh embodiment being an electronic instrument towhich the present invention is applied. The electronic instrument shownin FIG. 9 is an LCD module, and includes a liquid crystal panel 120, asemiconductor chip 122, and a substrate 124. The semiconductor chip 122includes the drive circuit for the liquid crystal panel 120. The presentinvention is applied to the adhesion construction of the semiconductorchip 122 and the substrate 124. The semiconductor chip 122 is mounted onthe substrate 124 to constitute a semiconductor device. For the mountingof the semiconductor chip 122, COF (Chip On Film) is applied. As aresult, the substrate 124 is a flexible film of thickness for exampleapproximately 25 μm. Such a substrate 124 has, for example, a pluralityof interconnect pattern elements formed by patterning on the film in amatrix form, to which those parts of the interconnect pattern not to beelectrically connected have a resist provided, and individual elementsof the interconnect pattern are formed by cutting out.

FIG. 10 shows details of the semiconductor device in this embodiment. Onthe substrate 124, a plurality of leads 126 and a film 128 are formed.The leads 126 are electrically connected to the liquid crystal panel120.

Except for its shape, the description in the first embodiment alsoapplies to the film 128. The film 128 is formed to avoid at least one(one or a plurality) of the leads 126. To the film 128 may be connectedat least one (one or a plurality) of the leads 126.

The film 128 comprises a first portion disposed within the region of thesurface of formation of electrodes 130 of the semiconductor chip 122,and a second portion projecting outside that region. In the firstportion, the electrodes 130 of the semiconductor chip 122 (preferablybumps) may contact the film 128 and be electrically conductivetherewith. In this case, the whole of the film 128 may be at groundpotential (GND potential).

Alternatively, the first portion may be formed to avoid the electrodes130. For example, when the first portion has formed concave portions toavoid the electrodes 130, the leads 126 may extend into the concaveportions, and within the concave portions the electrodes 130 may bebonded to the leads 126.

Of the film 128, since the second portion projects outside from thesurface of formation of the electrodes 130 of the semiconductor chip122, bubbles generated within the adhesive adhering the semiconductorchip 122 and the substrate 124 tend to be dispersed on the film 128 andreleased to the exterior.

The electronic instrument shown in FIG. 9 may have at least oneelectronic component 132 mounted. The method of manufacture of such anelectronic instrument comprises a step of mounting the semiconductorchip 122 on the substrate 124, a step of mounting the electroniccomponent 132, and a step of connecting the substrate 124 on which thesemiconductor chip 122 is mounted to a liquid crystal display panel 120.

For the mounting of the semiconductor chip 122, facedown bonding usingfor example an anisotropic conductive material may be applied. For themounting of the electronic component 132, SMT (Surface Mount Technology)may be applied, carrying out brazing or soldering through a reflowprocess. To reduce or eliminate contamination of the substrate 124, thebrazing step is preferably carried out as late as possible in theprocess.

In all of the embodiments described above, the region in which theadhesive is disposed includes a region of low adhesion with the adhesivesuch as, for example the film or interconnect pattern, and a region ofhigh adhesion with the adhesive such as the base material of thesubstrate. To limit the generation of holes and voids, it is sufficientto ensure that: area of region of low adhesion≧area of region of highadhesion.

It should be noted that the above-described “semiconductor chip” of thepresent invention may be replaced by “electronic element,” and anelectronic component can be manufactured by mounting an electronicelement (whether an active element or a passive element) on thesubstrate in the same way as a semiconductor chip. As electroniccomponents manufactured using such an electronic element may be cited,for example, optical elements, resistors, capacitors, coils,oscillators, filters, temperature sensors, thermistors, varistors,variable resistors, and fuses.

1. A method of manufacture of a semiconductor device, comprising thesteps of: providing an adhesive between a surface of a semiconductorchip having a plurality of electrodes on which said electrodes areprovided and a surface of a substrate having a plurality of leads and anundivided film on which said leads and said undivided film are formed;positioning at least one of said plurality of electrodes to be opposedto at least one of said plurality of leads such that said undivided filmis opposed to said semiconductor chip; and applying pressure in adirection such as to make a gap between said semiconductor chip and saidsubstrate narrower such that said adhesive extends to be disposed on thewhole of said undivided film; wherein said undivided film is formed witha lower adhesion to said adhesive than a base material of saidsubstrate, and said undivided film is broader than each of said leads attheir portions opposed to said electrodes, and said undivided film isformed to be electrically isolated from both said electrodes and saidleads, wherein a region on which said adhesive is disposed includes afirst region with low adhesion to said adhesive and a second region withhigh adhesion to said adhesive, an area of said first region≧an area ofsaid second region.
 2. The method of manufacture of a semiconductordevice as defined in claim 1, wherein said adhesive is formed of ananisotropic conductive material having conductive particles dispersed inan insulating material.
 3. The method of manufacture of a semiconductordevice as defined in claim 1, wherein said leads and said undivided filmare formed by etching a conductive foil adhered to said base material ofsaid substrate.
 4. The method of manufacture of a semiconductor deviceas defined in claim 1, wherein a conductive foil used when forming saidleads is also used to form said undivided film.
 5. The method ofmanufacture of a semiconductor device as defined in claim 4, whereinsaid undivided film is formed simultaneously with said leads.
 6. Themethod of manufacture of a semiconductor device as defined in claim 1,wherein said electrodes are provided on an extremity of said surface ofsaid semiconductor chip; and wherein said undivided film is formed in aregion opposing a central part of said surface of said semiconductorchip.
 7. The method of manufacture of a semiconductor device as definedin claim 1, wherein said undivided film is formed to spreadtwo-dimensionally, with at least one opening exposing a surface of saidsubstrate.
 8. The method of manufacture of a semiconductor device asdefined in claim 1, wherein said undivided film is formed to projectoutside a region in which said semiconductor chip is adhered.
 9. Themethod of manufacture of a semiconductor device as defined in claim 1,wherein said undivided film is formed to be symmetrical about a centerpoint of a region in which said semiconductor chip is adhered.
 10. Themethod of manufacture of a semiconductor device as defined in claim 1,wherein said undivided film is formed to avoid at least one of saidleads.
 11. A semiconductor device comprising: a semiconductor chiphaving a plurality of electrodes; a substrate on which is formed aplurality of leads and an undivided film, said undivided film opposed tosaid semiconductor chip and electrically isolated from both saidelectrodes and said leads; and an adhesive provided between a surface ofsaid semiconductor chip on which said electrodes are formed and asurface of said substrate on which said leads and said undivided filmare formed to adhere said semiconductor chip and said substrate, saidadhesive disposed on the whole of said undivided film, wherein at leastone of said plurality of electrodes and at least one of said pluralityof leads are electrically connected; and wherein said undivided film isformed with a lower adhesion to said adhesive than a base material ofsaid substrate, and said undivided film is broader than each of saidleads at their portions opposed to said electrodes, wherein a region onwhich said adhesive is disposed includes a first region with lowadhesion to said adhesive and a second region with high adhesion to saidadhesive, an area of said first region≧an area of said second region.12. The semiconductor device as defined in claim 11, wherein saidadhesive is formed of an anisotropic conductive material havingconductive particles dispersed in an insulating material.
 13. Thesemiconductor device as defined in claim 11, wherein said leads and saidundivided film are formed of the same electrically conductive material.14. The semiconductor device as defined in claim 11, wherein saidelectrodes are provided at an extremity of said surface of saidsemiconductor chip; and wherein said undivided film is formed in aregion opposing a central part of said surface of said semiconductorchip.
 15. The semiconductor device as defined in claim 11, wherein saidundivided film is formed to spread two-dimensionally, with at least oneopening exposing a surface of said substrate.
 16. The semiconductordevice as defined in claim 11, wherein said undivided film is formed toproject outside a region in which said semiconductor chip is adhered.17. The semiconductor device as defined in claim 11, wherein saidundivided film is formed to be symmetrical about a center point of aregion in which said semiconductor chip is adhered.
 18. Thesemiconductor device as defined in claim 11, wherein said undivided filmis formed to avoid at least one of said leads.
 19. A circuit board onwhich is mounted the semiconductor device as defined in claim
 11. 20. Anelectronic instrument having the semiconductor device as defined inclaim 11.